High-perveance W-band sheet-beam electron gun design

Abstract

A design methodology for sheet-beam formation and solenoidal magnetic field transport is described, and a point design for a W-band amplifier gun and beam transport is presented. The gun topology flexibly permits adjustment of beam width to accommodate various interaction circuits while maintaining beam height. This topology has been employed in the design of a 19.5 kV, 3.6 A (1.32 mu-perv.) gun with beam final cross-section of approximately 4.2 mm x; 0.32 mm, using the 3-D gun code MICHELLE in conjunction with the magnet code MAXWELL-3D. Beam thermal effects due to cathode temperature are also included in the simulation.